<template>
  <div class="cart">
    <h4>全部商品</h4>
    <div class="cart-main">
      <div class="cart-th">
        <div class="cart-th1">全部</div>
        <div class="cart-th2">商品</div>
        <div class="cart-th3">单价（元）</div>
        <div class="cart-th4">数量</div>
        <div class="cart-th5">小计（元）</div>
        <div class="cart-th6">操作</div>
      </div>
      <div class="cart-body">
        <ul class="cart-list" v-for="cart in cartInfoList " :key="cart.id">
          <li class="cart-list-con1">
            <input type="checkbox" name="chk_list" :checked="cart.isChecked==1" @click="changestate(cart)">
          </li>
          <li class="cart-list-con2">
            <img :src="cart.imgUrl">
            <div class="item-msg">{{cart.skuName}}</div>
          </li>
          <li class="cart-list-con4">
            <span class="price">{{cart.skuPrice}}</span>
          </li>
          <!-- 实现点击加减和在输入框输入数据后只需要派发一个actons，向服务器发送请求修改商品数量-->
          <!-- 这里有个注意点在模版给函数传一个字符串时需要用单引号，双引号会报错 -->
          <li class="cart-list-con5">
            <a href="javascript:void(0)" class="mins" @click="handerskuNum('jian',-1,cart)">-</a>
            <input autocomplete="off" type="text" :value="cart.skuNum" minnum="1" class="itxt"  @blur="handerskuNum('change',$event.target.value,cart)">
            <a href="javascript:void(0)" class="plus" @click="handerskuNum('add',1,cart)">+</a>
          </li>
          <li class="cart-list-con6">
            <span class="sum">{{cart.skuPrice*cart.skuNum}}</span>
          </li>
          <li class="cart-list-con7">
            <a href="javascript:"  class="sindelet" @click="deletelist(cart.skuId)">删除</a>
            <br>
            <a href="#none">移到收藏</a>
          </li>
        </ul>
      </div>
    </div>
    <div class="cart-tool">
      <div class="select-all">
        <input class="chooseAll" type="checkbox" :checked="isallcheck" @click="allcheck()">
        <span>全选</span>
      </div>
      <div class="option">
        <a href="javascript:void(0)" @click="deleteChecked()">删除选中的商品</a>
        <a href="#none">移到我的关注</a>
        <a href="#none">清除下柜商品</a>
      </div>
      <div class="money-box">
        <div class="chosed">已选择
          <span>{{n}}</span>件商品</div>
        <div class="sumprice">
          <em>总价（不含运费） :</em>
          <i class="summoney">{{sumprice}}</i>
        </div>
        <div class="sumbtn">
          <a class="sum-btn" target="_blank" @click="tradeall()">结算</a>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
// 引入节流函数
import {throttle} from 'lodash'
import {onMounted,toRefs,reactive,computed,ref,watchEffect} from 'vue'
import {useStore}from 'vuex'
import {useRouter} from 'vue-router'
  export default {
    name: 'ShopCart',
    setup() {
      const store =useStore()
      const router = useRouter()
      onMounted(()=>{
        store.dispatch("CartList")
      })
      let {cartInfoList}={...toRefs(reactive(store.getters))}
     console.log(cartInfoList);
      //  计算是否全部勾选
     let isallcheck = computed({
       get(){
         if(Array.isArray(cartInfoList.value)){//由于计算属性在渲染时数据还没回来，会报every方法错误，所以需要先判断是否是一个数组
           return cartInfoList.value.every(item=>{//数组的every方法：根据条件循环数组，只有全部数组元素都满足条件才返回true，否则返回false
         return item.isChecked==1
       })
         }
         else{
           return undefined
         }
       },
       set(value){
         console.log(value);
       }
       })
      //  修改购物车中的商品数量后派发action,这里需要节流防止用户快速点击
  let handerskuNum= throttle(async function(type,number,cartitem){
       switch (type) {
         case "jian":
          number= cartitem.skuNum>1?-1:0
           break;
        case "add":
           number=1
           break;
       case "change":
        //  修正输入的数量
           if(isNaN(number)||number<1){
           number=0
        }
        else{ 
        number=parseInt(number)-cartitem.skuNum
        }
           break;
       }
       try {
        //  判断是否修改数量成功，如果成功则再重新请求一次购物车数据
         await store.dispatch('AddcartList',{id:cartitem.skuId,sum:number})
         store.dispatch("CartList")
       } catch (error) {
         console.log(error.message);
       }
      
      },1000)  
     //  删除商品
   async function deletelist(skuId){
        try {
          await store.dispatch("DeleteCartlist",skuId)
          store.dispatch('CartList')
        } catch (error) {
          console.log(error.message);
        }
    }
    // 修改商品状态
    async function changestate(cart){
       try {
          await store.dispatch("ChangeState",{skuId:cart.skuId,state:cart.isChecked==0?1:0})
          store.dispatch('CartList')
        } catch (error) {
          console.log(error.message);
        }
    }
    // 删除已选中的商品
    function deleteChecked(){
     cartInfoList.value.forEach(item => {
      if (item.isChecked) {
        deletelist(item.skuId)
      }
     });
    }
    // 全选
      function allcheck(){
        cartInfoList.value.forEach(item=>{
           store.dispatch('ChangeState',{skuId:item.skuId,state:1})
            store.dispatch('CartList')
        })
    }
      // 点击结算跳到订单结算页
      function tradeall(){
            router.push({path:'/trade'})
      }
    
      let n = ref(0) // 计算选中的商品数量
      let sumprice=ref(0)// 计算选中的商品总价----通过watchEffect监视数据，商品数量发生改变就重新计算数量和总价
   watchEffect(()=>{
       n.value=0//检测到数量发生改变需要重新计算数量
       sumprice.value=0
     if (Array.isArray(cartInfoList.value)) {
       cartInfoList.value.forEach(item => {
      if (item.isChecked) {
        n.value+=item.skuNum
        sumprice.value+=item.skuNum*item.skuPrice
      }
     });
     }
    })
     return{
       cartInfoList,isallcheck,n,sumprice,
       handerskuNum,deletelist,changestate,deleteChecked,allcheck,tradeall
     }
    }
  }
</script>

<style lang="less" scoped>
  .cart {
    width: 1200px;
    margin: 0 auto;

    h4 {
      margin: 9px 0;
      font-size: 14px;
      line-height: 21px;
    }

    .cart-main {
      .cart-th {
        background: #f5f5f5;
        border: 1px solid #ddd;
        padding: 10px;
        overflow: hidden;

        &>div {
          float: left;
        }

        .cart-th1 {
          width: 25%;

          input {
            vertical-align: middle;
          }

          span {
            vertical-align: middle;
          }
        }

        .cart-th2 {
          width: 25%;
        }

        .cart-th3,
        .cart-th4,
        .cart-th5,
        .cart-th6 {
          width: 12.5%;

        }
      }

      .cart-body {
        margin: 15px 0;
        border: 1px solid #ddd;

        .cart-list {
          padding: 10px;
          border-bottom: 1px solid #ddd;
          overflow: hidden;

          &>li {
            float: left;
          }

          .cart-list-con1 {
            width: 15%;
          }

          .cart-list-con2 {
            width: 35%;

            img {
              width: 82px;
              height: 82px;
              float: left;
            }

            .item-msg {
              float: left;
              width: 150px;
              margin: 0 10px;
              line-height: 18px;
            }
          }

          .cart-list-con4 {
            width: 10%;

          }

          .cart-list-con5 {
            width: 17%;

            .mins {
              border: 1px solid #ddd;
              border-right: 0;
              float: left;
              color: #666;
              width: 6px;
              text-align: center;
              padding: 8px;
            }

            input {
              border: 1px solid #ddd;
              width: 40px;
              height: 33px;
              float: left;
              text-align: center;
              font-size: 14px;
            }

            .plus {
              border: 1px solid #ddd;
              border-left: 0;
              float: left;
              color: #666;
              width: 6px;
              text-align: center;
              padding: 8px;
            }
          }

          .cart-list-con6 {
            width: 10%;

            .sum {
              font-size: 16px;
            }
          }

          .cart-list-con7 {
            width: 13%;

            a {
              color: #666;
            }
          }
        }
      }
    }

    .cart-tool {
      overflow: hidden;
      border: 1px solid #ddd;

      .select-all {
        padding: 10px;
        overflow: hidden;
        float: left;

        span {
          vertical-align: middle;
        }

        input {
          vertical-align: middle;
        }
      }

      .option {
        padding: 10px;
        overflow: hidden;
        float: left;

        a {
          float: left;
          padding: 0 10px;
          color: #666;
        }
      }

      .money-box {
        float: right;

        .chosed {
          line-height: 26px;
          float: left;
          padding: 0 10px;
        }

        .sumprice {
          width: 200px;
          line-height: 22px;
          float: left;
          padding: 0 10px;

          .summoney {
            color: #c81623;
            font-size: 16px;
          }
        }

        .sumbtn {
          float: right;

          a {
            display: block;
            position: relative;
            width: 96px;
            height: 52px;
            line-height: 52px;
            color: #fff;
            text-align: center;
            font-size: 18px;
            font-family: "Microsoft YaHei";
            background: #e1251b;
            overflow: hidden;
          }
        }
      }
    }
  }
</style>